Maria Callas was the first artist to be publicly sacked by New York's Metropolitan Opera. La Scena Musicale Online's own columnist Norman Lebrecht is the latest.

I should have been broadcasting coast-to-coast this weekend, but cultural differences intervened. Some weeks ago I took a call from a BBC executive in London asking me to appear on the Metropolitan Opera broadcasts, which have been going out from New York on Saturday afternoons since Christmas 1931. 'Forget it,' I laughed. 'The Met talks are deeply reverential and my kind of take on opera is not going to be their cup of tea.'

On the contrary, said my chap. The Met were aware of a need to liven up the gap between acts. It had asked Radio 3 for a stimulating opinion former. The Beeb nominated me and the Met clapped its hands with glee, stipulating only that I should stick to commenting on opera in Britain and Europe - nothing within an ocean's reach of Lincoln Center.

There was an obvious reason for this outbreak of openness. The Met broadcasts are in trouble, living on borrowed time. Texaco, sponsors for 60 years, turned off the tap in 2003. Two private foundations provided grants for the current season but, unless new interest is generated through a more modern agenda, the Met will go silent on Saturdays and 40 relay partners around the world will lose their cheap weekend opera fix. Beverly Sills, the Met chair, has launched a $150 million national appeal, but the future of the broadcasts hangs in the balance. I could hardly refuse to help out.

Then came the second call, a couple of weeks ago. Embarrassed clearing of BBC throat. Terribly sorry, Norman, but the Met have asked us to take you off the broadcast. Something you've written, apparently.

It seems hardly worth investigating whether it was Gelb, Sills, or one of their over-eager acolytes who banned me from the broadcasts. The Met's curse is unlikely to blight my life, as it did the careers of many artists. My only surprise was that it hadn't happened before. In a quarter of a century of reporting musical affairs and commenting on them polemically, I have never been censored. I have been threatened with legal writs and, once, with a fist in my face, but no arts organisation until now has ever felt it necessary to shut me up.

In the corrupt Karajan era at Salzburg I exposed all manner of shenanigans, yet I was always welcomed back the following year and given access to all areas. One Covent Garden chief urged my editor over lunch to 'tone down' my accounts of the ROH's Nineties disarray; he was told not to be so silly and have another glass of claret. Even London's longest-running farce, the South Bank, which has taken almost 20 years to agree to a fudged plan to renew its sordid premises - even the South Bank has never taken me off its Christmas list.

So why has the Met so wildly over-reacted? The reason is, as you'd expect, cultural - and it illustrates the gulf that divides Europe and America over free speech in the arts. The Met is America's largest performing arts company, outspending all rivals by so vast a margin that no singer can make an impression on the US market without first triumphing there. Those who offend the management are brutally punished.

Maria Callas was the first to be publicly banned, in 1958, for irritating the Met manager Rudolf Bing, who vilified her in a defamatory press release. Callas was 35 at the time. Apart from two Toscas in 1965, She never sang another opera in the US - America's loss more than hers. Bing won full backing from his wealthy board and held his job for another 14 years.

In February 1994, the turbulent Afro-American soprano Kathleen Battle was sacked for what the Met boss, Joseph Volpe, called 'unprofessional actions ... profoundly detrimental to artistic collaboration'. Despite support from the Met's music director James Levine, Battle, then 46, was ruined. International dates dried up. Last month, she cancelled a rare UK appearance in Manchester. Battle was sunk by the Met's malevolence.

Roberto Alagna and Angela Georghiu, though now restored, were seriously maimed by an earlier sacking. Jonathan Miller, dismissed by Volpe after challenging Cecilia Bartoli over an otiose Mozart aria she interpolated in a 1998 Marriage of Figaro, said the Met had treated him high-handedly: 'I'd been fired.' One could cite any number of instances of genuine artistic differences which, at the Met, were settled not by reasoned, open debate but by summary firing squad.

The key difference between European and American practice in the performing arts is the question of accountability. Sustained partly or largely by state subsidy. European companies acknowledge a civic duty to act transparently and respond constructively to public criticism. Relations with the media are not always comfortable, but there is an assumed collegiality in the transaction: arts organisations do their job, we do ours. Even a private festival like Glyndebourne practises a form of glasnost.

The American attitude to the press is more feudal. Companies like the Met exist because, says Beverly Sills, 'there is such a thing as American know-how. When you want to get things done, we don't turn around and say "Who's here to do it for us? " We do it ourselves.'

The doers, though, are the super-rich and they don't like being second-guessed. The plutocrats who sustain companies like the Met truss up the local media by persuading their owners that the arts are funded as a public benefice and should be treated like charities at Christmas time, with free space and good cheer. The result is an unrivalled munificence on stage and an absence on page of the fiery debate that keeps Europe's arts simmering in the public arena. The Met broadcasts are dulled down by design, eliminating the possibility of informed dissent. Enlightenment is impossible in the monolithic Met. I feel privileged to join its legion of the banned.